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Present status and future directions:Apexification

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World Journal of Methodology 2025年第1期15卷 26-32页

作者： Sachin Chauhan Radha Chauhan Prashant Bhasin Bhavna G Sharaf Department of Conservative Dentistry and Endodontics Sudha Rustagi College of Dental Sciences and ResearchFaridabad 121002HaryanaIndia Department of Prosthodontics and crown and bridge and Oral Implantology Mahatma Gandhi Dental College&HospitalJaipur 302022RajasthanIndia Department of Pedodontics and Preventive Dentistry Sudha Rustagi College of Dental Sciences and ResearchFaridabad 121002HaryanaIndia

The success rate of apexification is primarily determined by multiple factors,including the material used,the size of the open apex compared to the length of the root,and the technique used in each *** main objective of this review was to provide an update on the present management of open apex to identify factors and circumstances that may influence the success of apexification using different materials and *** research on apexification should focus on how to treat open apices with wide periapical lesions without ***,the predictability of these parameters with non-surgical procedures was uncertain,but now,with the use of a dental operating microscope,it has become more *** reason could be that extra visits are no longer required due to major advances in the armamentarium and materials used for apexification.

关键词： Bioceramics Magnification Biodentine Mineral trioxide aggregate Apexification Open apex

Effect of Self-adhesive Resin Cement and Tribochemical Treatment on Bond Strength to Zirconia

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International Journal of Oral Science 2010年第1期2卷 28-34页

作者： Akikazu Shinya Harunori Gomi Akiyoshi Shinya Department of crown and bridge School of Life Dentistry at TokyoThe Nippon Dental University

Aim To evaluate the interactive effects of different self- adhesive resin cements and tribochemical treatment on bond strength to zirconia. Methodology The following self-adhesive resin cements for bonding two zirconia blocks were evaluated： Maxcem （MA）, Smartcem （SM）, Rely X Unicem Aplicap （UN）, Breeze （BR）, Biscem （BI）, Set （SE）, and Clearfil SA luting （CL）. The specimens were grouped according to conditioning as follows： Group 1, polishing with 600 grit polishing paper; Group 2, silica coating with 110 μm Al2O3 particles which modified with silica; and, Group 3, tribochemical treatment - silica coating ＋ silanization. Specimens were stored in distilled water at 37℃ for 24 hours before testing shear bond strength. Results Silica coating and tribochemical treatment significantly increased the bond strength of the MA, UN, BR, B1, SE and CL to zirconia compared to #600 polishing. For both #600 polished and silica coating treatments, MDP- containing self-adhesive resin cement CL had the highest bond strengths to zirconia. Conclusion Applying silica coating and tribochemical treatment improved the bond strength of self-adhesive resin cement to zirconia, especially for CL.

关键词： self-adhesive resin cement zirconia silica coating tribochemical treatment bond strength

Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static Loading Experiment

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Structural Durability & Health Monitoring 2025年第1期19卷 105-123页

作者： Zhao-Jun Zhang Wen-Wei Wang Jing-Shui Zhen Bo-Cheng Li De-Cheng Cai Yang-Yang Du Hui Huang Offshore Oil Engineering Co.Ltd. Tianjin300461China Department of bridge Engineering School of TransportationSoutheast UniversityNanjing211189China

This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment *** experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was *** composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab *** methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel *** experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal *** contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading *** the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan *** the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span *** GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span *** test specimens experienced compressive failure of concrete at the mid-span *** results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support *** proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs.

关键词： Moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model

A new spatial coherence model and analytical coeffi cients for multi-support response spectrum combination

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Earthquake Engineering and Engineering Vibration 2007年第3期6卷 225-235页

作者：王君杰陈虎 Dept. of bridge Engineering Tongji University

In this paper, a new spatial coherence model of seismic ground motions is proposed by a fitting procedure. The analytical expressions of modal combination （correlation） coefficients of structural response are developed for multi-support seismic excitations. The coefficients from both the numerical integration and analytical solutions are compared to verify the accuracy of the solutions. It is shown that the analytical expressions of numerical modal combination coefficients are of high accuracy. The results of random responses of an example bridge show that the analytical modal combination coefficients developed in this paper are accurate enough to meet the requirements needed in practice. In addition, the computational efficiency of the analytical solutions of the modal combination coefficients is demonstrated by the response computation of the example bridge. It is found that the time required for the structural response analysis by using the analytical modal combination coefficients is less than 1/20 of that using numerical integral methods.

关键词： multi-support seismic excitations spatial coherence model modal combination coefficients computational efficiency power spectrum density

Effects of fundamental factors on coupled vibration of wind-rail vehicle-bridge system for long-span cable-stayed bridge

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Journal of Central South University 2016年第5期23卷 1264-1272页

作者：张明金李永乐汪斌 Department of bridge Engineering Southwest Jiaotong University

In a wind-vehicle-bridge(WVB) system,there are various interactions among wind,vehicle and *** mechanism for coupling vibration of wind-vehicle-bridge systems is explored to demonstrate the effects of fundamental factors,such as mean wind,fluctuating wind,buffeting,rail irregularities,light rail vehicle vibration and bridge stiffness.A long cable-stayed bridge which carries light rail traffic is regarded as a numerical ***,a finite element model is built for the long cable-stayed *** deck can generally be idealized as three-dimensional spine beam while cables are modeled as truss *** are modeled as mass-spring-damper *** irregularities and wind fluctuation are simulated in time domain by spectrum representation ***,aerodynamic loads on vehicle and bridge deck are measured by section model wind tunnel *** vertical and torsional flutter derivatives of bridge deck are identified by weighting ensemble least-square ***,dynamic responses of the WVB system are analyzed in a series of *** results show that the accelerations of the vehicle are excited by the fluctuating wind and the track irregularity to a great *** transverse forces of wheel axles mainly depend on the track *** displacements of the bridge are predominantly determined by the mean wind and restricted by its *** the accelerations of the bridge are enlarged after adding the fluctuating wind.

关键词： wind-vehicle-bridge system coupled vibration long-span cable-stayed bridge fundamental factors

ELASTIC-PLASTIC ANALYTICAL SOLUTIONS FOR AN ECCENTRIC CRACK LOADED BY TWO PAIRS OF ANTI-PLANE POINT FORCES

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Applied Mathematics and Mechanics(English Edition) 2003年第7期24卷 782-790页

作者：王成吴承平 bridge Department Chongqing Jiaotong University

The improved near crack line analysis method was used to investigate an eccentric cracked plate loaded by two pairs of anti_plane point forces at the crack surface in an elastic_perfectly plastic solid. The analytical solutions of the elastic_plastic stress fields and displacements near the crack line have been found without the assumptions of the small scale yielding. The law that the length of the plastic zone along the crack line is varied with an external loads and the bearing capacity of an eccentric cracked plate are obtained.

关键词： eccentric cracked plate near crack line analysis two pairs of anti_plane point forces elastic_plastic analytical solutions

Mechanical behavior of concrete filled glass fiber reinforced polymer-steel tube under cyclic loading

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第11期14卷 778-788页

作者： Chun-yang ZHU Ying-hua ZHAO Shuang GAO Xiao-fei LI Institute of Road and bridge Engineering Dalian Maritime University

The mechanical behavior of concrete-filled glass fiber reinforced polymer(GFRP)-steel tube structures under combined seismic loading is investigated in this study. Four same-sized specimens with different GFRP layout modes were tested by a quasi-static test system. Finite element analysis(FEA) was also undertaken and the results were presented. Results of the numerical simulation compared well with those from experimental tests. Parametric analysis was conducted by using the FE models to evaluate the effects of GFRP thickness, axial compression rate, and cross sectional steel ratio. The experimental and numerical results show that the technique of GFRP strengthening is effective in improving the seismic performance of traditional concrete-filled steel tubes, with variations related to different GFRP layout modes.

关键词： Concrete-filled glass fiber reinforced polymer(GFRP)-steel tube Seismic Energy dissipation Stiffness degradation

Research development of digital maintenance and management system for long-span cable-stayed bridges

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Journal of Harbin Institute of Technology(New Series) 2009年第1期16卷 96-100页

作者：任远黄侨孙永明 Institute of bridge Engineering Harbin Institute of Technology Institute of bridge Engineering Southeast University

Digital cable-stayed bridge maintenance and management system （DCBMS） was developed for the need of maintenance and management of long-span cable-stayed bridges. In this paper, the major functions and theoretical application of eight modules were systematically stated with the background of Harbin Songhua River cable-stayed bridge, which include data management module, inspection and measurement module, assessment module, finite dement analysis module, disease diagnosis and prediction module, maintenance module, query module and help module. By analyzing and calculating the data from manual inspection database, basic database and health monitoring subsystem, DCBMS can accomplish the functions like life prediction, disease diagnosis, comprehensive assessment, maintenance and management of bridges. Therefore, the maintenance and management of long-span cable-stayed bridges can be made digital, professional and scientific. By running this system, a real-time and specific technical guidance can be provided for the maintainers and managers of long- span cable-stayed bridges.

关键词： cable-stayed bridges system development maintenance and management comprehensive assessment disease diagnosis

Study on the seismic performance of a double spherical seismic isolation bearing

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Earthquake Engineering and Engineering Vibration 2008年第4期7卷 439-446页

作者： Peng Tianbo Li Jianzhong Xu Yan Fan Lichu Department of bridge Engineering Tongji University Shanghai 200092 China

In this paper, the configuration and working mechanism of the recently developed double spherical seismic isolation （DSSI） bearing are introduced in detail. Then, vertical displacement of the DSSI bearing due to sliding on a spherical surface is analyzed. The results from seismic performance testing of the bearing are given, and a numerical analysis of a four span continuous girder bridge is performed. The numerical analysis compares the influence of three different bearing arrangement schemes on the structural seismic response, and the results show that the DSSI bearing is effective in increasing the vertical load bearing capacity, reducing the vertical displacement, and controlling the energy dissipation capacity within a certain range.

关键词： DSSI bearing seismic isolation vertical displacement energy dissipation continuous girder bridges